AD/CESSNA 560/5 - AFM Icing Information and Angle of Attack Computer

Overview

The Civil Aviation Regulations 1998, specifically under Part 39 - 105, were enacted to address safety issues within the aviation sector, ensuring that aircraft meet stringent safety standards. In 2000, the Civil Aviation Safety Authority (CASA) issued an Airworthiness Directive (AD) in response to reports of uncommanded roll incidents in Cessna 560 series aeroplanes, particularly in icing conditions. The AD was designed to rectify safety deficiencies identified by the Federal Aviation Administration (FAA) by mandating revisions to the Airplane Flight Manual (AFM) and modifications to the angle-of-attack computer in the stall warning system. The policy objective was to mitigate the risk of uncommanded rolls during critical phases of flight, thereby enhancing overall flight safety. This AD became effective on 3 April 2000, requiring specific actions to be taken within stipulated timeframes to address the identified unsafe conditions.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 under the Civil Aviation Safety Authority, include Airworthiness Directives that govern the maintenance and operational safety of specific aircraft models within Australia. This particular directive applies to Model 560 series aeroplanes, specifically those with serial numbers 560-0001 through 560-0437 inclusive. The directive mandates that the Airplane Flight Manual (AFM) be updated as specified, with different revisions required for aeroplanes within different serial number ranges. Additionally, the stall warning system of the angle-of-attack computer must be modified according to Service Bulletins, again with variations depending on the aeroplane’s serial number. Furthermore, the directive prohibits the installation of certain angle-of-attack computers on any aeroplane. Compliance timelines are set, with AFM revisions needing to be completed within ten days of the directive’s effective date, modifications to the stall warning system within six months, and the prohibition on specific angle-of-attack computers taking immediate effect. This directive is designed to address safety concerns related to uncommanded roll during approach and landing when residual ice is present or can be expected, thereby enhancing the overall safety of the specified aircraft models within the Australian aviation industry.

Key Provisions

The Airworthiness Directive (AD) issued under subregulation 39.1(1) of the Civil Aviation Regulations 1998 (CAR 1998) applies to Model 560 series aeroplanes with serial numbers (S/N) ranging from 560-0001 through 560-0437 inclusive (AD/CESSNA 560/5). The directive requires specific actions to be taken to address identified safety concerns, particularly related to icing conditions and uncommanded roll during flight operations. The AD mandates three key requirements: the revision of the Airplane Flight Manual (AFM) for specific serial number ranges, the modification of the stall warning system angle-of-attack computer, and the prohibition of installing certain angle-of-attack computers on the aircraft. First, the directive mandates the revision of the AFM. For aeroplanes with serial numbers 560-0001 through 560-0259 inclusive, the AFM must be revised to Model 560 Citation V, Revision 11, dated 16 July 1998. For aeroplanes with serial numbers 560-0260 through 560-0437 inclusive, the AFM must be revised to Model 560 Citation V Ultra, Revision 7, dated 16 July 1998. Second, the stall warning system of the angle-of-attack computer of the navigational system must be modified. For aeroplanes with serial numbers 560-0001 through 560-0055 inclusive, the modification must comply with Cessna Service Bulletin (SB) 560-34-70, dated 14 July 1998. For aeroplanes with serial numbers 560-0056 through 560-0437 inclusive, the modification must comply with Cessna SB560-34-69, Revision 2, dated 24 July 1998. Lastly, angle-of-attack computers with part numbers C11606-2 or C11606-3 are prohibited from being installed on any aeroplane. Compliance with this AD is mandatory and must be achieved within specified timeframes. For Requirement 1, the AFM revisions must be completed within ten days of the AD's effective date. For Requirement 2, the modifications to the stall warning system must be completed within six months of the effective date. For Requirement 3, the prohibition on specific angle-of-attack computers must be implemented as of the effective date of the AD. The AD becomes effective on 3 April 2000, as notified in the Commonwealth of Australia Gazette on 15 March 2000. Failure to comply with the AD may result in significant consequences. The AD does not explicitly state penalties or legal consequences for non-compliance, but non-compliance with ADs can lead to severe repercussions, including potential grounding of the aircraft, civil penalties, or criminal charges. Operators and owners of affected aircraft must adhere to the AD's requirements to ensure continued airworthiness and compliance with safety regulations.